Printing machine



Nov. 4, 1941;

L.. B. CASE PRINTING MACHINE1 Filed sept. 12, 193s.

ATTORNEYS.

Patented Nov. 4, 1941l PRINTING MACHINE Lynn B. Case, New Brunswick, N. J., assignor to John Waldron Corporation, New Brunswick, N. J., a corporation of New Jersey Application September 12, 1939, Serial No. 294,412

(ol. i- 152) vz owns.

This invention relates to printing machines md more especially to printing machines using hot melt ink, that is, ink solidat normal temperature and liquid at elevated temperature.

In printing machines using soluble ink, no provision is made for regulating lthe temperature of the printing cylinder and a rubber sur face impression cylinder is commonly used. However, the use of hot melt ink requires` that the temperature ofv the printing cylinder be maintained above the solidication temperature of the hot melt ink, such temperature being above that at which rubber may be satisfactorily used as the impression surface.

An object of this invention is a printing machine equipped with an 'impression cylinder' pression surface is unaifectedlby vthe`tem13erature to which it is subjected `in printing with hot melt ink, The surface of the impression cylinder is continuously conditioned by means of a smooth surface metal roll having rolling` contact with the impression cylinder surface and applying pressure thereto.

Other objects, novel features and advantages of this invention will become apparent from the following specification and accompanying drawing, wherein:

Fig. 1 is a sectional view of an apparatus embodying the invention;

Fig. 2 is a longitudinal sectional view of the impression cylinder, and

Fig. 3 is a diagrammatic elevational view of the printing cylinder, impression cylinder and conditioning cylinder. y

In the drawing is illustrated schematically a printing machine equipped with a plurality of Aengraved printing cylinders, only two of which are shown. The printing cylindersare all of the same size and means are provided for driving said cylinders all at the same speed. Also, means are provided for. supplying heat to the interior `of theprintin'g cylinders for maintaining the surfaces thereof at a predetermined temperature, depending upon the composition of the hot melt ink used.

Each printing cylinder lilis partially enclosed by a pan Il containing hot melt ink and heating means I2 are provided for maintaining the ink at proper temperature. A doctor I3 is associated with each printing cylinder I0 for removing excess ink therefrom. An impression cylinder I4 .is associated with each printing cylinder III and is driven in synchronism with the printing cylinder by suitable means, not shown. The impression cylinder comprises a roll of compressed fibrous material, the surface of which 'with each impression cylinder I 4 and. is driven in synchronism therewith by suitable means. The roller I5 has rolling contact with the impression cylinder M 'and is so arranged as to apply pressure thereto for the purpose oi contin uously conditioning the surface of the roller Il to maintain it suitable for use as an impression surface. A scraper or doctor I8 engages the roll I5 for scraping from it any brous or other material which may adhere to it from contact with the impression cylinder Il.

Apair of rollers I 'I and I 8 are provided for guiding the web I2 between the printing and impression cylinders and for maintaining the web under proper tension. Means are provided f for effecting adjustment of the roll I8 so as to vary the area of contact of the web with the while the pan heating means I 2 is shown as a hot water' or steam jacket, other types `of heating means may be used.

Preferably, the roller Il is composed of paper in the form of a large number of annular sheets encircling a steel shaft. In forming the roll, the

paper sheets are subjected toa very highfdegree 'I'he paper sheets may, therefore, contain various percentages of felt, various grades of cotton or even asbestos nbre.

Means, not shown, are provided for regulating the heat suppliedto the ink heating means I2 and to the cylinders ID and are effective to maintain each cylinder I0 o! the machine at the same temperature as each remaining cylinder irrespective of the number of cylinders that there may be in the machine. Such means preferably consists of thermostats properly placed to be responsive to the temperature of the ink and the peripheral temperature of the cylinder in combination with means controlled by the thermostat for regulating the heat supply means. The cylinders are maintained at the same temperature to insure that they expand to the same extent and that they have equal circumferences during operation of the machine. Were the cylinders to thereby prevent proper registration of successive impressions on the paper and eiecting either rupture or wrinkling of the paper.

1 I claim:

1. In a hot melt ink printing machine, a heated printing cylinder, an impression cylinder composed of compressed brous material, a smooth face `metal roll having rolling contact with said impression cylinder and applying pressure thereto, and a doctor Vco-operating with said roll for removing brous material therefrom.

2. In a hot melt ink printing machine, a heated printing cylinder, an impression cylinder beat diierent temperatures they would have uncomposed of a plurality of highly compressed annular sheets of fibrous material, a. smooth face metal roll having rolling contact with said impression cylinder and applying pressure thereto, and a doctor co-o'perating with said roll for ramoving fibrous material therefrom.

LYNN B. CASE. 

